1. Field of the Invention
The invention relates to a light emitting diode (LED) structure, more particularly to a LED structure by employing the nanorods-like structure to raise the light emission efficiency.
2. Description of the Prior Art
Due to the one of the character light emitting diode (LED) is the high light emission efficiency, thus there is the higher potential to become the illumination equipment of the new generation. However, if the present illumination equipments are going to be totally substituted, the light emission efficiency of LED will be highly raised, so that the high brightness LED brightness can be made. One of the best solutions is to produce the nanorods-like structure for LED.
In the prior art, the nanorods-like structure formed in LED can be used to release the stress, and reduce the piezoelectric effect. The formation of the nanorods-like structure can also increase the sidewall-surface area to raise the light emission efficiency.
However, most of the nanorods-like structure is formed directly by the crystal growth in materials science. For example, The hydride vapor phase epitaxy (HVPE) or the formation of GaN-nano-rod can be used. In addition, the etching technology can also be used to produce the nanorods-like structure, such as using E-Beam and Inductively Coupled Plasma (ICP) method to produce the nanorods-like structure. However these methods can not produce the nanorods-like structure in which the electric current can be injected to generate the light emitting component with nanorods-like structure.
For the technology disclosed in the previous literature, there is a U.S. Pat. No. 7,132,677B2 about “Super bright light emitting diode of nanorods array structure having InGaN quantum well and method for manufacturing the same”. The GaN-based nano-rod having quantum well structure is used in this patent. The gap among nano-rod is filled by Spin-On Glass (SOG), and only p-type semiconductor is exposed at the top. The metal layer is coated to form ohm contact and to get light emitting element. Though the nanorods-like structure generated by the structure can be used to excite the LED, the epitaxy is utilized to form the mechanism of nanorods-like structure. The hydride vapor phase epitaxy (HVPE) is different from the metal organic chemical vapor deposition (MOCVD) for the formation of LED, there will be have technical problem in future application.
In addition, the conventional light emitting component with nanorods-like structure can not be formed as good LED, because the etching surface of nanorods-like structure high resistance value.